Seasonal occurrence and diversity of arthropods in Bt cotton ecosystem under Akola conditions of Maharashtra

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1 2017; 5(5): E-ISSN: P-ISSN: JEZS 2017; 5(5): JEZS Received: Accepted: AA Shinde Department of Entomology, SM Dadmal Department of Entomology, ND Gajbe Anand Niketan College of Agriculture, Warora Dist.- Chandrapur, Maharashtra, VA Mane Department of Botany, Seasonal occurrence and diversity of arthropods in Bt cotton ecosystem under Akola conditions of Maharashtra AA Shinde, SM Dadmal, ND Gajbe and VA Mane Abstract Present investigation was carried out at Department of Entomology, Dr. PDKV Akola (MS) during kharif It is revealed from the survey that, Bt cotton ecosystem harbored total 22 insect fauna out of which 14 insects were categorized as pests and 8 were natural enemies (NEs), besides eight species of predatory spiders were recorded. In Bt cotton ecosystem whiteflies, leafhoppers, aphids, mite, thrips, red cotton bugs were found in abundance during 34 th, 35th, 36th SMW. Whereas, natural enemies viz; spiders, lady bird beetles, mallada, syrphid fly, ant and chrysopa were found predominantly during 35 th, 36 th, 37 th and 38 th SMW. The simple correlation studies indicated that rainfall had a significantly negative correlation with semilooper, whitefly, leafhopper population. However, positive significant association was noticed between maximum relative humidity with fruit borer, ash weevil, syrphid fly, white flies, chafer beetle and spider population. High percent abundance was recorded by aphids followed by leaf hoppers, whiteflies, mites, thrips and red cotton bugs with moderate to rich biodiversity of arthropod fauna was noticed in Bt cotton (H'= 2.193) crop ecosystem at Akola. Keywords: Kharif crop ecosystem, Bt cotton, natural enemies, pests, spiders, biodiversity 1. Introduction In agriculture is currently suffers an annual loss about US 36 billion due to insect pests. The last two decades have witnessed a remarkable progress in various bio-pesticide strategies including the development of transgenic crops. Such strategies should be utilized in IPM programme to reduce crop losses without affecting the quality of environment [1]. This heavy crop loss causes the farmer to use huge amounts of pesticides [2]. But, both the quantity of food loss due to pests and the cost of pest control in terms of money and human health are significant [3]. Cotton is major kharif crop it is also called the king of fiber crops. Major pest of cotton is American bollworm, spotted bollworm, pink bollworm, and sucking pests like leafhopper, whitefly, thrips, aphids, etc. However, bollworm menace as been tackled by introducing Bt cotton. Predatory arthropods growing wildly in fields are one of the natural sources of pest management. When natural enemies are abundant in cotton field, higher pest levels can be tolerated for longer periods without pesticide use that means there is a saving of pest control cost. Predatory fauna including spiders play an important role crops pests management [4]. is one of the hotspots of arthropods biodiversity in the world. The diversity plays an important role in the functioning of an agro-ecosystem. At present, scanty information is available on the changing pest scenario and bio-agent insect fauna in kharif crop agroecosystem. Looking into the significance of major pest, bio-agent fauna the present study was undertaken to explore the insect pests and predatory fauna of an agro- ecosystem of Akola in relation to its diversity. This work aimed to emphasize the need for conservation of the diversity of predatory insect fauna found in a major kharif crop ecosystem for estimating the species diversity as well as the present status of insect pest fauna. Correspondence AA Shinde Department of Entomology, 2. Materials and methods The present study was carried out at Department of Entomology, Post Graduate Institute Dr. Panjabrao Deshmukh Krishi Vidyapeeth Akola, during Insects are generally inactive or less active in morning hours hence most of the collection was under taken during morning hours. Arthropods were searched on the Bt cotton crop. ~ 1614 ~

2 2.1 observations recorded A weekly survey of Bt. cotton recorded from each block. Wherever, adult stage occurred were collected and preserved for identification in the Taxonomy laboratory Department of Entomology. Immature stage of pests was brought to the Lab for further rearing. Collected fauna were identified at Biosystematics Lab., Department of Entomology Dr. P.D.K.V. Akola. 2.2 Correlation between meteorological parameters and pests/ natural enemies at Akola The population of pests and natural enemies were correlated with various weather parameters. For correlation studies data of weather parameters of preceding week were considered by the population of pests and natural enemies of current week. 2.3 Shannon biodiversity index Considering the occurrence of varied type of species of pests and natural enemies in Bt cotton ecosystems at Akola, the same data was used to estimate the diversity index for generic level / species level by following Shannon diversity index using following formula s H ' = - (Pi ln Pi) i=1 Pi= ni/n ni = number of individuals of species i N = total number of individuals of all species pi = relative abundance of species i S = total number of species H = Shannon Diversity Index 3. Results and Discussion 3.1 Arthropod fauna occurred in Bt cotton ecosystem: During the Kharif season of 2016, total twenty three arthropods (Insects and mites) were recorded (Table1). Out of them fourteen insects were categorized under pest and nine arthropod natural enemies were observed in the Bt cotton crop at Akola. Among fourteen insect pests six sap feeders viz; whitefly, leaf hoppers, aphids, thrips, mealy bug and mite, six chewers viz; blister beetle, chaffer beetle, grasshopper, ash weevil, Spodoptera, semilooper and one cotton bug i.e. red cotton bug and one bollworm i.e. pink bollworm were recorded. Among nine natural enemies lady bird beetle, spider, mallada, syrphid fly, chrysopa, ant, miridbug, mantid and dragonfly were recorded. Out of three bollworm only pink boll worm was recorded on Bt cotton. In Bt cotton ecosystem eight predatory spiders were recorded beside insect and mites (Table1.1) namely Argyrodes sp., Hyllus sp., Araneus sp., Thomisus sp., Telamonia sp., Oxyopes sp., Rhene sp., Clubiona sp. Some of the previous researchers have also reported insect fauna from different parts of. [5] have reported major predators in cotton ecosystem. These predators were coccinelids, mantid, syrphid fly and chrysoperla sp. They further reported that the sucking pests like aphids, jassids and thrips were effectively checked by these predators. Most of the insect - pests including mite were observed to be commonly recorded pests in this locality. However, among the predators miridbug was found active in Bt cotton ecosystem besides other common predators. Among the other arthropod predators spiders were active with diverged species and attempt was made first-time for identification of this important predatory arthropods. A total eight genera belonging to seven different families were recorded in Bt cotton ecosystem at Akola. reported four species of spiders in kharif agro-ecosystem in Akola district viz.; Neoscona sp., Oxyopes sp., Thomisus sp., Pseusetia sp. Out of which Oxyopes sp. and Thomisus sp. [4], same were also recorded during the present investigation endorsed the present findings. Table 1: Arthropod fauna occurred in Bt cotton ecosystem during Kharif 2016 in Akola Sr. Common name of Pests / Natural Species Family Order No. arthropods enemies 1 Leafhopper Amrasca biguttula biguttula (Ishida) Cicadellidae Hemiptera Pest 2 Whitefly Bemisia tabaci (Genn.) Aleyrodoidae Hemiptera Pest 3 Aphid Aphis gossypii (Glover) Aphididae Hemiptera Pest 4 Spodoptera Spodoptera litura (Fabricius) Noctuidae Lepidoptera Pest 5 Thrips Thrips tabaci (Lindeman) Thripidae Thysanoptera Pest 6 Semilooper Anomis flava (Fabricius) Erebidae Lepidoptera Pest 7 Ashweevil Myllocerus dentifer (Fabricius) Curculionidae Coleoptera Pest 8 Mite Tetranychus sp. Tetranichidae Trombidiformes Pest 9 Mealybug Phenacoccus solenopsis (Tinsley) Pseudococcidae Hemiptera Pest 10 Grasshopper Hieroglyphus nigrorepletus (Bolivar) Acrididae Orthoptera Pest 11 Blister beetle Mylabris phalerata (Pallas) / M. pustulata (Thunb.) Meloidae Coleoptera Pest 12 RCB Dysdercus koenigii (Fabricius) Pyrrhocoridae Hemiptera Pest 13 Chafer beetle Oxycetonia versicolor (Fabricius) Scarabeidae Coleoptera Pest 14 PBW Pectinophora gossypiella (Saunders) Gelechiidae Lepidoptera Pest 15 LBB Cheilomenes sexmaculata (Fabricius) Coccinellidae Coleoptera Natural enemies 16 Syrphid fly Ischiodon scutellaris (Fabricius) Syrphidae Diptera Natural enemies 17 Spider (List enclosed in separate Table) Araneae Natural enemies 18 Chrysopa Chrysoperla sp. Chrysopidae Neuroptera Natural enemies 19 Ant - Formicidae Hymenoptera Natural enemies 20 Mantid Mantis sp. Mantidae Mantodea Natural enemies 21 Mallada Mallada sp. Chrysopidae Neuroptera Natural enemies 22 Dragonfly - Aeshnidae Odonata Natural enemies 23 Miridbug - Miridae Hemiptera Natural enemies ~ 1615 ~

3 Table 1.1: Spiders occurred in Bt cotton ecosystem during Kharif 2016 in Akola Sr. No. Name Family Order Pests / Natural enemies 1. Argyrodes sp. Theridiidae Araneae Predator 2. Hyllus sp. Salticidae Araneae Predator 3. Araneus sp. Araneidae Araneae Predator 4. Thomisus sp. Thomisidae Araneae Predator 5. Clubiona sp. Clubionidae Araneae Predator 6. Telamonia sp. Salticidae Araneae Predator 7. Oxyopes sp. Oxyopidae Araneae Predator 8. Rhene sp. Salticidae Araneae Predator 3.2 Seasonal occurrence of pest of Bt cotton ecosystem During the course of study, fourteen insect species viz., leafhopper (Amrasca biguttula biguttula), whiteflies (Bemisia tabaci), aphids (Aphis gossypii), tobacco leaf eating caterpillar (Spodoptera litura), thrips (Thrips tabaci), green semilooper (Anomis flava), ashweevil (Myllocerus dentifer), mite (Tetranychus sp.), mealy bug (Phenacoccus solenopsis), grasshopper (Hieroglyphus nigrorepletus), blister beetle (Mylabris phalerata / M. pustulata), red cotton bug (Dysdercus koenigii), chafer beetle (Oxycetonia versicolor) and pink bollworm (Pectinophora gossypiella) were recorded (Fig. 1 & 2) under pest category on Bt cotton. The incidence of leafhoppers was noticed from 28 th SMW to 49 th SMW and peak incidence was recorded (11 leafhoppers / leaf) in 37 th SMW. The whitefly infestation was initiated in 29 th SMW increased upto 37 th SMW and then decreased thereafter and peak was noticed during 37 th SMW. The incidence of aphids was from 29 th SMW to 52 nd SMW and it was increased gradually and peak incidence recorded (22 / leaf) during 52 nd SMW. The incidence of spodoptera was recorded from 29 th SMW to 31 st SMW but it was meager in Bt cotton. The incidence of thrips was initiated from 30 th SMW to 52 nd SMW, it was increased gradually and peak incidence was recorded (4.9 thrips / leaf) in 37 th SMW. The incidence of green semilooper was recorded from 32 nd SMW to 3 th SMW but it was very meager. The incidence of ash weevil was recorded from 35 th SMW to 48 th SMW with peak population 0.8 per plant recorded in 38 th, 39 th, 43 rd SMW. The incidence of mite was recorded from 37 th SMW to 41 st SMW and peak population was 14.6 mite per leaf during in 40 th SMW. The incidence of mealy bug was noticed from 37 th SMW to 42 nd SMW. The incidence of grasshopper was recorded from 38 th SMW to 47 th SMW and peak population 0.6 per plant was recorded in 42 nd SMW. The incidence of blister beetle was recorded from 39 th SMW to 43 rd SMW. The incidence of red cotton bug was noticed from 41 st SMW to 52 nd SMW and it was increased gradually and peak incidence was recorded during 48 th SMW. The incidence of chaffer beetle was recorded from 41 st SMW to 44 th SMW. The infestation of pink boll worms was initiated from 44 th SMW with peak population of 0.6 larvae per plant during 47 th SMW. It means that, infestation of pink boll worm has initiated on Bt cotton at late season although it was low infestation. Extremely low larval population of pink bollworm in Bt. cotton throughout the crop season [6]. Aphids incidence was noticed from 33 rd SMW to till end of the season with some intermittent out breaks. Leafhopper incidence was also recorded from 33 rd to 43 rd SMW. In case of thrips peak was recorded in 35 th SMW [7]. Thus, the present finding is in close proximity with the previous findings. 3.3 Seasonal occurrence of natural enemies in Bt cotton ecosystem During the course of study, nine species, viz, lady bird beetle (Cheilomenes sexmaculata), syrphid fly (Ishiodon scutellaris), spiders, chrysopa (Chrysoperla sp.), ant, mantid (Mantis sp.), mallada (Mallada sp.), dragonfly and mirid bug, were recorded (Fig.3) as the natural enemies in Bt cotton. The activity of LBB was noticed from 31 st SMW to 51 st SMW and it was increased gradually with a peak population during 37 th SMW. The population of syrphid fly was recorded from 32 nd SMW to 43 rd SMW and it was increased gradually with a peak during 35 th and 36 th SMW. The activity of spiders was noticed from 33 rd SMW to 52 nd SMW and increased gradually to a peak population (0.8 /plant) recorded during 37 th SMW. Chrysopa were active from 33 rd SMW to 43 rd SMW and peak population was recorded in 36 th SMW. The occurrence of mantid was recorded from 34 th SMW to 47 th SMW. The activity of mallada was noticed from 37 th SMW to 43 rd SMW and it was increased gradually with a peak population (0.6 per plant) recorded in 39 th SMW. The occurrence of the dragonfly was recorded from 37 th SMW to 40 th SMW. The population of mirid bug was recorded from 39 th SMW to 50 th SMW to a peak populations (3.2 bugs /plant) recorded in 44 th SMW. In Bt cotton ecosystem seven species of spiders were found active in Akola for taking care of sucking pests beside other natural enemies need to be conserved. Forty natural enemies per 50 plants of cotton were recorded in Integrated Pest Management module. The population of natural enemies was comprised of coccinellids, syrphid fly, chrysopa and spider had taken care of sucking pests [8]. Thus, the present investigation is in the tune to the previous finding. Fig 1: Seasonal occurrence of sucking pests in Bt cotton ecosystem during ~ 1616 ~

4 Fig 2: Seasonal occurrence of foliage feeders in Bt cotton ecosystem during Fig 3: Seasonal occurrence of natural enemies in Bt cotton ecosystem during Correlation between insect population and weather parameters in Bt cotton ecosystem The simple correlation studies recorded that there was a relationship between arthropod population and weather parameter in the Bt Cotton crop ecosystem (Table 2). Minimum temperature (r = ), WS (r = ) and RH II (r = ) had a negative significant correlation with aphids population. Whereas, BSH showed a positive significant correlation (r = 0.517) with aphids population. Evaporation showed a positive significant correlation (r= 0.587) with thrips population. Maximum temperature (r = 0.918) and BSH (r = 0.824) showed positive significant correlation with semiloopers population. Whereas, RH I (r = ), RH II (r = ) and RF (r = ) showed a negative significant correlation with semiloopers population. Minimum temperature (r = ) and RH II (r = ) showed negative significant correlation with population of mite. Whereas, BSH (r = 0.647) and evaporation (r = 0.818) had significantly positive correlation with mite population. Maximum temperature (r= 0.496) and minimum temperature (r = 0.505) had positive significant correlation with mealy bug population. Whereas, BSH (r = ) showed significant negative correlation with mealy bug population. Maximum temperature showed positive significant correlation (r = 0.612) with blister beetle. Whereas, WS (r = ) and RH II (r = ) showed a significantly negative correlation with blister beetles population. WS showed a negative significant correlation (r = ) with red cotton bug population. Maximum temperature (r = ), minimum temperature (r = ), WS (r = ) and evaporation showed a significantly negative correlation with population of pink boll worm. Minimum temperature (r = 0.663), WS (r = 0.798) and evaporation (r = 0.496) showed positive significant correlation with lady bird beetles population. RF (r = ) showed negative correlation with syrphid flies population. Minimum temperature (r = 0.663), WS (r = 0.798) and RH II (r = 0.491) showed a significantly positive correlation with population of spider. Maximum temperature (r = 0.767) and BSH (r = 0.571) showed a positive significant correlation with population of chrysopa. Whereas, Minimum temperature (r = ), WS (r = ), RH I (r = ) and RH II (r = ) showed negative significant correlation with chrysopa population. RF (r = 0.529) showed significantly positive correlation with mallada population. Whereas, BSH (r= ) showed negative significant correlation with mallada population. Minimum temperature (r = 0.612), RH II (r = 0.504) and RF (r = 0.539) showed positive significant correlation with ant population. RH I (r = 0.740), RH II (r = 0.500) and RF (r= 0.852) showed positive significant correlation with dragonfly population. Whereas, Maximum temperature (r = ), WS (r = ) and evaporation (r = ) showed negative significant ~ 1617 ~

5 correlation with dragonfly population. In Bt cotton genotypes, maximum and minimum temperature showed significant and positive effect on whitefly population, whereas the relative humidity exerted a negative effect during 2010 [9]. During 2011, the effect of all the factors was not noticed. On a cumulative basis, there was a positive non-significant correlation between population of whitefly and minimum temperature. During the present investigations also whitefly had non-significant weak correlations with abiotic factors except evaporation (r 0.467). A weak but negative correlation was noticed with RH I which is in tune to the previous finding. Rain fall had negative but weak correlation with whitefly. Whereas, minimum temperature, relative humidity and bright sunshine hour showing positive but weak correlation with whitefly population [10]. BSH had a weak negative correlation with leafhoppers which endorsed the present investigations. Table 2: Correlation between arthropod population and weather parameters in Bt. cotton ecosystem in Akola during the kharif 2016 Insect T MAX T MIN BSH WS RH I RH II Evap RF Leafhopper * * Whitefly * Aphid ** 0.517** ** ** Thrips ** Semilooper 0.918** ** ** ** 0.479* ** Ashweevil 0.417* Mite ** 0.647** 0.775* ** 0.818** Mealybug 0.496** 0.505** ** * Grasshopper Blisterbeetle 0.612** * ** * ** RCB * ** * Chaffer beetle 0.917** ** 0.907** ** ** ** 0.744** ** PBW ** ** ** ** - LBB ** * 0.798** * 0.496** Syrphid fly * ** Spider ** ** 0.394* 0.491** 0.448* 0.382* Chrysopa 0.767** ** 0.571** * ** ** ** Ant ** * ** ** Mallada * ** * * 0.529** Dragonfly ** ** 0.740** 0.500** ** 0.852** Miridbug 0.433* ** ** * Significant correlation at 5% (r = 0.381), ** Significant correlation at 1% (r = 0.487) Table 3: Shannon biodiversity index of arthropod fauna in Bt. cotton ecosystem in Akola during the kharif 2016 Name of Species Av.no. of insect recorded Percent abundance Pi ln Pi Pi ln Pi Leafhopper Whitefly Aphid Spodoptera Thrips Semilooper Ashweevil Mite Mealybug Grasshopper Blisterbeetle RCB Chaferbeetle PBW LBB Syrphid fly Spider Chrysopa Ant Mantid Mallada Dragonfly Miridbug Total H' = Shannon biodiversity index of arthropod fauna in Bt cotton crop ecosystem Shannon diversity index (Table 3) revealed that the percent abundance of sucking pests viz; cotton aphids Aphis gossypii was percent followed by leafhopper (13.74%), whiteflies (8.6%), mite (8.28%) and thrips (6.96%) in descending order. Thus, the sucking pests complex shared more than 75 percent population of arthropod fauna. Red cotton bug; a stainer on cotton boll shared (4.18 percent). Population of the pink boll worm was meager (0.50 ~ 1618 ~

6 percent).among the predators mirid bug showed 5.01 per cen, LBB (2.82%), ant (2.57%), syrphid fly (1.16%), chrysopa (1.37%) and mallada (0.41%). Spider shared (1.53%) abundance and had more species diversity. A rich Shannon diversity index (H' = 2.193) was recorded in Bt cotton ecosystem at Akola comprising twenty three different arthropods fauna. 5. Conclusions Under Akola conditions of Maharashtra in the Bt cotton ecosystem no significant changing scenario is observed in terms of in terms of insect pests status. However, the population of predatory fauna seems to be declined. Activities of predatory spiders are a noteworthy.abiotic factor plays an important role on the activities of both pests and predatory arthropods fauna. Biodiversity index of arthropods in Akola was moderate to rich. 6. Acknowledgement We are thankful to Dr. A. K. Shirbhate, Asstt. Professor of Zoology, Shankarlal Khandelwal Science College, Akola for identification of spider specimens collected during the course of the investigation. 7. References 1. Dhaliwal GS, Jindal Vikas, Mohindru Bharathi. Crop Losses due to insect pests: Global and n Scenario. n J. Entomology. 2015; 77(2): Akhtar MW, Sengupta D, Chowdhury A. Impact of pesticide use in n Agri. their benefits and hazards. Interdisciplinary Toxicology. 2009; 2(1): Pimentel D, Greinier A. Environmental and socioeconomic costsof pesticide use. In D. Pimentel (Ed.), Reducing Pesticides: Env. and Eco. Benefits, Chichester, UK: John Wiley & Sonspp. 1997, Naikwadi Bhausaheb, Dadmal SM, Javalage Samadhan. Diversity study of predaceous insect fauna in major kharif crop agro-ecosystem in Akola Maharashtra () The Bioscan. 2015; 10(4): Menon MV, Thangavelu K. Survey of beneficial arthopod in cotton ecosystem at Coimbatore, South. Entomon. 1979; 4(3): Lavekar RC, Telang SM, Sharma OP, Rathod KS. Efficacy of pesticides against field insect pests of Bt cotton. Annals of Plant Protection Sci. 2004; 12(2): Annual Report Department of Entomology, Dr. P.D.K.V. Akola, RRC.2017, Submitted to Research Review Committee, Plant protection held on, Rao V, Rao BR, Rajasekhar P, Venkatataih M. Development of integrated pest management module for cotton in Andhra Pradesh. J. Bio. Control. 1995; 9(2): Akram M, Hafeez F, Farooq M, Arshad M, Hussain M, Ahmed S et al. A case to study population dynamics of Bemisia tabaci and Thrips tabaci on Bt and non-bt cotton genotypes, Pak. J Agri. Sci. 2013; 50(4): Annual Report, Department of Entomology, Dr. P.D.K.V. Akola, RRC 2011, Submitted to Research Review Committee, Plant protection held on, ~ 1619 ~

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